johnson



(No Model.)

I. G. JOHNSON.

PAVEMENT. No. 340,123. Patented Apr. 20, 1886.

I I T: h 7i UNITED. STATES PATENT OFFICE.

FRANK G. JOHNSON, OF NEYV YORK, N. Y.

PAVEMENT.

lEEY-PECIPICATION forming part of Letters Patent No. 340,123, datedApril 20, 1886.

Serial No. 177,325. (No model.)

To all whom, it may concern.-

Be it known that I, FRANK G. JOHNSON, a citizen of the United States,residing in the city, county, and State of New York, have invented a newand useful Improvement in Pavements, of which the following is aspecification.

My invention relates to that class of improvements in pavements whichhas for its chief object a flat and smooth surface without sacrificingfoothold and durability or reuden ing it too expensive to be afforded. Iattain these objects by the method illustrated in the accompanyingdrawings, making a part of the specification, in which- Figure l is atopview; Fig. 2, a vertical section showing part of the apparatus formaking the pavement; Fig. 8, a top view of Fig. 2; Fig. 4, a top view ofthe pavement, enlarged; and Fig. 5, a perspective view of a metallicframe.

Similarlettcrs referto similarparts throughout the several views.

The pavement consists nf.three parts: first, a foundation, which,preferably, may consist of cobble or other stones, because they arecheap, and for the reason that in many cities they are alreadylaid;second, a dressing consisting of broken or crushed stone broken intofragments ranging about from the size of a hazelnut to that of abutternut, spread over the foundation and rammed down and leveled off,and sufficiently thick to level up and conceal the cobble-stones orother suitable foundation; and, third, melted or molten iron poured uponand into the dressing, whereby the interstices between the brokenfragments are filled and the fragments of stone are joined together, thefragments of stone and iron forming a level stone and iron concrete overthe foundation. The iron uniting the fragments inseparably together andthe broken stone, being the ma jor part of the bulk of material abovethe foundation, afford sufficient friction for the horse. Besides, asthe broken stone will wear down a little faster than the iron,additional foothold will be thus secured, while the generalsurface willbe practically fiat and smooth.

The concrete dressing of stone and iron, instead of being laid or madecontinuous, is divided into squares of a yard or so across, (shown inFig. 1,) in a manner hereinafter explained, in order to facilitate thelaying and the taking up of the pavement.

A more detailed description of the construction of the pavement isdescribed as follows:

A A A, Fig. 1, represent the upper surface of the pavement divided intosections about a yard square, the three squares on the left showing thefragments of broken stone, which arealso better illustrated byb b binFig. 4, in which figure a a a represent the iron be tween the fragmentsof broken stone, only that for clearness of representation the spacesbetweenthefragmenls are relatively too large in the illustration. Thisdisproportion be tween the-iron and broken stone, and for the samereason, obtains in the view Fig. 2, as when the broken stone is properlyrammed down (before the melted iron is poured on) the proportion ofbroken stone to the iron in bulk is about as one to six or eight, oreven greater, depending upon how closely the broken stone is rammedbefore being concreted by pouring the iron.

B B, Figs. 1 and 2, represent the foundation shown in the drawings ascobble-stones.

D D, Figs. 2 and 5, represent a frame the size of the squares in Fig. 1,consisting of a narrow strip of thin sheet-iron bent at right angles,which istermed the moldingframe.

C C, Fig. 2, represent a metallic plate bent down at right angles on theedges and lined or tilled with molding-sand c 0, through which is agateway, d, to pour the melted iron upon the broken stone. This plate,for convenience, is termed the molding-plate, the top view of which isrepresented by Fig. 3.

The method of laying the pavement is described as follows: When thecobble-stone pavement is all ready laid, and is to be employed as thefoundation, the loose dirt is first to be swept off, after which thecobble-stones are to be covered over for a considerable distance withthe broken stone sufficiently to conceal the crowns of thecobble-stones, and then to be well rammed down, to compact the fragmentsof broken stone as closely together as possible. Having done this, oneof the molding-frames (D D, Figs. 2 and 5) is then driven down edgewiseinto the broken stone until it strikes the cobble-stones, leaving theupper edge flush with the rammed broken stone. The molding-plate, (C 0,Figs. 2 and 3,) being somewhat larger in area than themoldingframe (D D,Figs. 2 and 5) and lined with molding-sand, is laid on the edge of themoldiu ;-frameand over the broken stone contained therein. This beingdone, the melted iron is now to be run through the pouring-gate d, Figs.2 and 3. The iron being hardened by cooling, the molding-plate isremoved and the molding-frame remains. Thus one section or square of thepavement being laid and finished, other sections are laid around andcontiguous to the first, and so on.

The molding-frame divides the pavement into square sections, which canbe taken up here and there as required for laying gas, water, steam, andother pipes.

A portable furnace, of course, is employed for melting the iron.

Other materials besides crushed stone-for instance, ironslag, or amixture of crushed stone and iron-slitg-may be employed with the meltediron. Therefore I do not limit myself to the use of crushed stone\viththe. melted iron; neither do limit myself to, the

stone 1) b, substantially in the manner and for the purposes described.

2. In the construction of pavements, the

combination of melted iron a a, crushed stone b b, and thefouudation-stoneB B, substantially as and for the purpose set forth.

3. In the construction of pavements, the combination of melted iron an,crushed stone 1) b, and moldingframe D D D, substantially as and for thepurpose described.

FRANK G. JOHNSON.

Witnesses:

J NO. J. MALMAR, E. H. ADAMS.

